Leaf and stem micromorphology of Jacquemontia evolvuloides (Moric.) Meisn. (Convolvulaceae) populations: New insights for taxonomic classification using light and scanning electron microscopy

Morphoanatomical studies can provide useful and relevant information to support taxonomic groupings. Jacquemontia evolvuloides shows great morphological variability, which has led to numerous taxonomic classifications. To determine if anatomical characters can be used to recognize operational taxonomic units within populations of that species, we analyzed the leaves and stems of 22 populations using light and scanning electron microscopy. The variability of the analyzed characters allowed the grouping of these populations into five morphotypes. The presence of paracytic stomata, laticiferous canals, and stellate trichomes can be considered diagnostic characters of J. evolvuloides. The presence and types of epicuticular waxes, as well as a layer similar to palisade parenchyma in the petioles and stems, the classifications of glandular trichomes, and new types of stomata (anomocytic, anomotetracytic, and brachyparatetracytic) are reported here for the first time for Jacquemontia. The results discussed here help clarify the classification of this species complex and contribute to the taxonomy of Jacquemontia-a genus that has historically been difficult to define due to its wide morphological variation at the species level.

Automated summary

Morphoanatomical studies were conducted on Jacquemontia evolvuloides to determine its taxonomic groupings. The analysis of leaf and stem morphology led to the identification of five morphotypes within 22 populations. Diagnostic characters such as paracytic stomata, laticiferous canals, and stellate trichomes were observed. Additionally, new findings on epicuticular waxes, palisade parenchyma-like layer, glandular trichome classifications, and new types of stomata were reported for Jacquemontia for the first time. These results provide valuable insights into the classification and taxonomy of Jacquemontia.